Concentric carburetor



1951 M. J. KITTLE R CONCENTRIC CARBURETOR Filed- Oct. 15, 1949 w wR E E Md lfiiiler I N V EN TOR.

FWTaQA/E Y Patented Aug. 14, 1951 2,564,113 CONCENTBIIC CARBURETOR Milton J. Kittler, Detroit, Mich., assignor to George M. Holley and Earl Holley Application October 15, 1949, Serial No. 121,545

2 Claims. (01. 261-23) 1 The object of this invention is to improve the atomization and distribution during normal running and during starting when the choke valve is partially or entirely closed to insure an adequate supply of fuel.

I have found that when the butterfly choke valve is located in the Venturi throat that the rich mixture nozzle should be located in the middle of the choke valve and should discharge downstream. If I also locate the choke valve in the center of the air stream then there is an interference. By stamping a semi-circular trough in the upstream half of the choke valve and providing a central circular opening in the choke valve to line up with the rich mixture nozzle I improve the ability of the choke valve to-gi ve the rich mixture needed for a quick start in cold weather but I also improve the atmoization and distribution of the fuel when the choke valve is under open conditions.

This case is a continuation in part of my copending application Serial No. 102,687, filed July 1, 1949.

Fig. 1 shows in cross-sectional elevation the preferred form of my invention with the air cleaner (silencer) removed. The location of the air cleaner (silencer) is shown in broken lines enclosing the float chamber.

Fig. 2 shows a cross-sectional elevation on plane 22 of Fig. 3. v

Fig. 3 shows in elevation the butterfly choke valve.

Fig. 4 shows the view .looking down on Fig. 3.

Fig. 5 shows a cross-sectional elevation on plane 5-5 of Fig. 1. I y

-In the figures I0 is the air entrance. I2 is the left hand venturi. I4 is the right hand venturi. A concentrically mounted choke shaft 28, controlled by the choke lever 22, engages with the right hand choke valve 24, which choke valve in its turn engages the intermediate choke shaft 26. Shaft 26 engages the left hand choke valve 28. The choke valve 28 engages the left hand choke shaft 30. The choke valve 24 is provided with ears 32, 34, 36 and 38 which serve to guide the left hand end of choke shaft 28 and the right hand end of intermediate shaft 26. The choke valve 24 is provided with a semi-circular depression 48. This semi-circular depression 48. embraces the nozzle I8. A circular opening 42, in the choke valve 24, provides a free path for the rich mixture to be drawn into the enginewhen the choke valve 24 is closed. A similar opening 44 is provided in the left hand choke valve":

The throttle shaft 46 carries butterfly throttles 48 and 68 and is controlled by the throttle lever 52. These two throttles control the mixture outlets 54 and 56. A float chamber 58 containing float 60 maintains a constant level in a well known manner. The float chamber 58 is supported on the flange 62 by a number of legs 63, 64, and 65 shown in Fig. 1. This flange 62 supports the usual air cleaner and air silencer as shown by broken lines.

Fuel for the rich mixture nozzles l6 and I8 is derived by air vented wells 66 and 68. These wells receive fuel through restrictions 10 and 12 and receive air through the air vents I4 and 16. The air passages 18 and 88 are open to the air entrance III. The air entering the passages 14 and 16 reaches the wells 66 and 68 through the perforated tubes 82 and 84. The air that flows through the rich mixture nozzles I6 and I8 enters through restrictions 86 and 88. The fuel leaves the air vented wells 66 and 68 through the inclined passages 98 and 92 and is atomized through the air flowing through the restrictions 86 and 88.

The low speed fuel passages 94 and 96 discharge through the openings 98, I80, I02 and I04. The outlets I00 and I84 at all times are in the mixture outlets 54 and 56. The outlets 98 and I82 are placed in communication with the mixture outlets 54 and 56 whenever the throttles 48 and 50 are moved away from the idling and into the low speed positions. The low speed passage 96 communicates with the chamber I 86 which receives air from a passage I08, connected to the air entrance Ill, and receives fuel from a fuel orifice H0. Fuel orifice H0 is connected to the bottom of the air vented well 68. The bottom of the air vented well 66 is connected to the low speed fuel restriction H2. The atomizing air for the low speed passage 94 is derived from the air passage H4.

Operation When the choke valves 24 and 28 are rotated clockwise (Fig. 5) the openings 42 and 44 are placed in line with the openings in the center of the rich mixture tubes l6 and I8. As the choke valve moves to the wide open position as shown in the drawing the degree of engine suction applied to the rich mixture tubes I6 and I8 gradually diminishes so that the normal mixture is gradually restored as the choke valves 24 and 28 are moved into the wide open position, in which they are shown.

WhatIclaim is:

1. In a carburetor a' 'casing containing a Venchoke valve is open, a central opening in said choke valve located so as to be insubstantial alignment with the open end of said tube when the choke valve is closed.

2. In a carburetor a casing containing two.

venturi air entrances in parallel, two tubes, each discharging a rich mixture downstream into the throat of the venturi associated therewith, said tubes being located substantially in central axial alignment with the-two venturisand terminating inhthe throatsthereof, a first choke shaft diametrically located so, asto project into the first Venturi throat, a. first butterfly choke valve mountedon the endof the choke, shaft second choke shaft, in axial alignment with the first .chokeshaft proiecting into both venturis and u engaging said first choke valve, a second butterfly 4 choke valve located in the throat of said second venturi and engaged by said second choke shaft, a third choke shaft engaged by said second choke valve and in axial alignment with the first and second choke shafts whereby the first and second choke valves are operated by the first choke shaft, an opening in the center of each choke valve, a depression formed in the upstream half of each choke valve so as to embrace half of the peripheral surface of each of the two rich mixture tubes when the choke valves are open and to place the openings in the two choke valves in alignment with the. two rich mixture tubes when the choke valves are closed.

' MILTON J. KIT'I'LER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,0 1,8 5, Gobb --o M y 1.3, 1,913 1,730,268 Constantinesco. e 0,019., .9 29 1,872,559 Bicknell Aug, 16, 1932 2,193,533 Kishline et a1 Mar. 12, 1940 

